It has long been known that absorbent articles such as conventional taped diapers offer the benefit of receiving and containing urine and/or other bodily exudates. To effectively contain exudates, the article should provide a snug fit around the waist and legs of a wearer. Absorbent articles are known to have a chassis comprising a topsheet, a backsheet, and an absorbent core. Absorbent articles such as conventional taped diapers generally include a front and a rear waist section releasably and/or refastenably connected by a fastening system. The fastening system generally comprises an engaging member and a receiving member. The engaging member may be an adhesive tape, a hook bearing tape, a cohesive tape, or other like structure. The receiving member may be an element or zone on the article that may receive the engaging member such as a polymer film landing zone (viz., for receipt of the adhesive or cohesive tape) or a loop bearing surface (viz., for receipt of the hook bearing tape). The engaging member may be joined to the receiving member thereby interconnecting the rear waist section to the front waist section and thereby forming a waist opening and a pair of leg openings.
Current diaper designs frequently include the use of extensible ears. Back ears may extend laterally from the longitudinal edge of the rear waist section of the chassis. The engaging member of the fastening system may be attached to the back ear. In the case of front-fastened or taped designs, when the fastening system is engaged to the receiving member on the front waist region, the back ear serves as an interconnecting member between the front waist section and the rear waist section, which together form a waist opening and pair of leg openings. Back ears may be constructed to provide a degree of elastic recovery. Elasticized back ears allow the diaper to provide a more customized fit. Furthermore, the elastic capability allows the diaper to adjust to the forces exerted by the wearer without causing permanent deformation of the diaper or discomfort for the wearer of the diaper. Elasticity is typically imparted to the back ears by incorporating elastic materials into the ear. Due to the high cost of elastomeric materials, a common practice is to construct elastic ears as discrete components that are attached to the chassis (i.e., the main absorbent assembly to which other components may be disposed) resulting in a multipiece diaper. While this practice results in the efficient and cost-effective use of elastic materials, it is not without problems.
One problem seen in multipiece diapers is “tophatting.” A “tophat” is a portion of the front or rear waist region that extends beyond the uppermost edge of the front or back ear toward the waist edge of the diaper. When a multipiece diaper is appropriately worn, the waist edge of the diaper in the front waist region and the rear waist region are substantially linear or slightly curvilinear. As the waist edge transitions from the rear waist region to the attached back ear, the waist edge may abruptly drop and then continue in a linear or curvilinear manner following the upper edge of the back ear. This “drop” from the waist edge in the front waist region or the rear waist region to the upper edge of the back ear may be one centimeter or greater. When worn, a taped diaper with the drop in the waist edge appears to have a notch cut from its side. The waist edge of such a diaper may have a stair step-like appearance.
Tophatting may have an adverse impact on the fit characteristics of a multipiece diaper. Generally, a diaper exerts a circumferential line of tension around a wearer's torso. This tension may be a product of the elastic back ear being strained. With a multipiece diaper exhibiting a tophat, the line of tension is located well below the waist edge because the line of tension is transmitted only along or through a continuous, unbroken path about the diaper. Since the tension-generating elasticized ear and fastening system are significantly remote from the waist edge, the line of tension is likewise remote from (e.g., generally lower than) the waist edge in the front waist region and rear waist region.
Fit and functionality problems may result from the line of tension being located remotely from the waist edge. For example, the front waist region and/or rear waist region of the diaper may exhibit sagging or fold-over. Sagging is the wrinkled, loose, gapped, or puckered configuration that the diaper exhibits when it is not under tension. Fold-over is the inversion of at least a portion of the diaper such that a body-facing surface of the diaper becomes garment-facing. Similar to sagging, fold-over may occur when the portion of the diaper is not under tension. Fold-over and sagging may also impair the gasketing function of the waist edge. For example, the interface of the waist edge and the wearer's waist is susceptible to leakage particularly when the wearer is in a prone or supine position. Fold-over and sagging can reduce the surface area of the diaper that is in close contact with the wearer at this interface which may result in leakage.
Furthermore, fold-over and sagging are aesthetically undesirable. Fold-over and sagging result in a diaper that is sloppy looking during wear. This, in turn, may communicate to the consumer that the diaper is of low quality which may be contrary to the high quality of functional characteristics such as absorbency or leakage prevention.
Top-hatting and the resulting lack of a smooth, continuous, and circumferential waist edge communicate other unwanted messages to the consumer or wearer of the diaper. For example, tophatting may be a readily visible signal that the product is a diaper. For many wearers such as children being toilet trained or incontinent youths and adults, a stigma is attached to having to wear a diaper. To alleviate this concern, the diaper should communicate a message of being garment-like or underwear-like. In other words, it is desirable that the diaper not appear diaper-like. However, tophatting and discontinuous waist edges are apparent signals of a diaper.
Accordingly, it would be desirable to provide a diaper having a back ear that eliminates or reduces tophatting in a multipiece diaper. Furthermore, it is desirable that the diaper exhibit a smooth, continuous, circumferential waist edge without discontinuities or drops. It is desirable that the diaper exhibit a line of tension, which is provided at least in part by discrete ears, as close to the waist edge as possible. It is also desirable that the diaper communicate a message of being garment-like without the readily apparent visual cue (e.g., waist discontinuity) of being a diaper.